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Low tech geothermal heating/cooling for solar powerhouse

mvonw

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Sep 23, 2019
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I have 5 acres and an excavator and decided it would fun to try a low-tech geothermal heating and cooling system by burying 600 feet of plastic water pipe down 8 feet and connecting to radiator/pump/fan in my shed that has my lifepo/inverters. I'm in a cold region and I figure I can stabilize the temperature in winter above freezing in my insulated shed and also cool for around 100watts for the pump and fan. Has anyone else ever done this?
 
I have not, but I installed a geothermal for my home, 35 years ago. You pump will draw less and pump more if you oversize your pipe. I put in 1400 feet of 2" and the friction calculator was showing zero friction losses. 1400 feet was for a 1600 sq ft house. I think you could get by with less than the 600 feet of pipe that you mentioned.
 
I have not, but I installed a geothermal for my home, 35 years ago. You pump will draw less and pump more if you oversize your pipe. I put in 1400 feet of 2" and the friction calculator was showing zero friction losses. 1400 feet was for a 1600 sq ft house. I think you could get by with less than the 600 feet of pipe that you mentioned.
I was considering 1.5" pipe. Perhaps If I half filled it with propylene glycol for 350 feet it would do the trick? I have to believe the flowrate of the pump is a factor too?
 
I was considering 1.5" pipe. Perhaps If I half filled it with propylene glycol for 350 feet it would do the trick? I have to believe the flowrate of the pump is a factor too?
Not sure if the flow rated is very critical. The fluid needs time underground and above ground to exchange heat. I have a little boiler pump on my unit and I think the flow is about 7gph.
 
I have not done what you are considering but do encourage others to do it whenever possible. Mother Earth is here to help, when we let her. I strongly agree with minimizing friction losses while in the design stage. Efficiency will be the key to success. (y) Go man go!

This is not totally on target, maybe useful info though:

Scroll down to the bottom of the page for "Similar threads". ;)
 
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I have not done what you are considering but do encourage others to do it whenever possible. Mother Earth is here to help, when we let her. I strongly agree with minimizing friction losses while in the design stage. Efficiency will be the key to success. (y) Go man go!

This is not totally on target, maybe useful info though:

Scroll down to the bottom of the page for "Similar threads". ;)
I've gone around the horn on this. Originally, I was considering constructing a root cellar to house the batteries, but decided against for cost and water infiltration reasons. I love the simplicity of cheap water pipe and cheap energy input of this approach!
 
this is my 2024-2025 project..... I need to buy the adjacent lot, my plan was to bury 3 meters down as the adjacent lot is a slope, so build a retaining wall from lava boulders and back fill was my plan. i just want to keep the underside fo the house above freezing in the winter, though I have considered disassembling a split pack and putting its condenser in there as well to make my cooling in the summer more efficient.
 
Methanol and water is better then glycol and cheaper.

I had access to a 6 foot deep trencher in the early 2000's and put in 4000 feet of 3/4 tubing in four parallels loops. System worked fine on a 3000 sq/ft house in lower Michigan. Half way through winter is would hit freezing in the loop and never go colder. Search "latent heat" and at the phase transition at freezing takes a lot of energy loose to freeze. Lived in that house for 15 years.

New house is geo "pump and dump" mainly for AC. We have Natural Gas for heating but am in the process now of putting in a mini split to use up my excess solar.
 
Methanol and water is better then glycol and cheaper.

I had access to a 6 foot deep trencher in the early 2000's and put in 4000 feet of 3/4 tubing in four parallels loops. System worked fine on a 3000 sq/ft house in lower Michigan. Half way through winter is would hit freezing in the loop and never go colder. Search "latent heat" and at the phase transition at freezing takes a lot of energy loose to freeze. Lived in that house for 15 years.

New house is geo "pump and dump" mainly for AC. We have Natural Gas for heating but am in the process now of putting in a mini split to use up my excess solar.
How many ton/BTU heater?
 
Mvonw, did you ever get to finish this experiment? I've been toying with this very idea but running it through my radiant slab floor in the garage (instead of radiator) to keep it above freezing and hopefully take the edge off of the 105 degree heat in the summer.
 
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